Control valve

ABSTRACT

A fluid system for controlling the operation of a fluid motor includes a pilot operated control valve. The pilot operated control valve has a valve portion for controlling the flow of pressurized fluid from a pressurized fluid supply to the fluid motor. The pilot operated control valve has a pilot portion associated with the valve portion for controlling the valve portion. A binary control valve is included in the fluid system and is operatively associated with the pilot portion of the pilot operated control valve. The binary control valve has a first position in which it directs a fluid signal to the pilot portion of the control valve and thereby effects operation of the fluid motor by controlling the valve portion. The binary control valve also has a neutral position in which no signal is provided to the pilot portion of the control valve. The fluid system also includes a manual control valve operatively associated with the pilot portion of the pilot operated control valve to override the control of the pilot operated control valve by the binary control valve.

United States Patent 1191 Jasinski et a1.

1 1 Nov. 12, 1974 1 1 CONTROL VALVE Machines Limited, 03, Woodstock,

Ontario, Canada 22 Filed:. Sept. 13 1972 [21] Appl. No.: 288,819

Related US. Application Data [63] Continuation of Ser. No. 27,549, April 13, 1970.

abandoned.

[52] US. Cl. 91/453, 91/461 [51] Int. Cl. FlSb 11/08, FlSb 13/042 [58] Field of Search 91/453, 367, 425, 306,

FOREIGN PATENTS OR APPLICATIONS 953,738 4/1964 Great Britain 251/26 Primary Examiner-lrwin C. Cohen Attorney, Agent, or Firm-Teagno & Toddy [57] ABSTRACT A fluid system for controlling the operation of a fluid motor includes a pilot operated control valve. The pilot operated control valve has a valve portion for controlling the flow of pressurized fluid from a pressurized fluid supply to the fluid motor. The pilot operated control valve has a pilot portion associated with the valve portion for controlling the valve portion. A binary control valve is included in the fluid system and is operatively associated with the pilot portion of the pilot operated control valve. The binary control valve has a first position in which it directs a fluid signal to the pilot portion of the control valve and thereby effects operation of the fluid motor by controlling the valve portion. The binary control valve also has a neutral position in which no signal is provided to the pilot portion of the control valve. The fluid system also includes a manual control valve operatively associated with the pilot portion of the pilot operated control valve to override the control of the pilot operated control valve by the binary control valve.

6 Claims, 3 Drawing Figures PATENTED MN 12 19m iii SHEET 10F 3 FIG! Pmmmm 12 em: 3.8471360 SHEET 20$ 3 CONTROL VALVE This is a Continuation, of application Ser. No. 27,549, filed Apr. 13, 1970 and now abandoned.

The present invention relates to a fluid system for controlling a fluid motor, and more particularly relates to a fluid system for automatically controlling a fluid motor which has provision for a manual override of the automatic control.

The present invention provides a fluid system for automatically controlling a fluid motor in an automatic or first operational mode and includes a manual control valve to override the automatic control of the fluid motor. The fluid system of the present invention includes a pilot operated control valve having a control valve portion for selectively conducting pressurized fluid from a pressurized fluid supply to the fluid motor, such that the motor may be driven in a predetermined direction. A pilot portion is included in the pilot operated control valve and is associated with the control valve portion to control the control valve portion and thereby determine in which direction the motor is moved.

A sensing device, such as a binary control valve, is operatively associated with the pilot portion to provide a signal to the pilot portion and has a first position to operate the pilot operated control valve such that the fluid motor moves in one direction in the automatic or first operational mode. The manual control valve is operatively associated with the pilot operated control valve such that when it is actuated, the control of the pilot operated control valve by the binary valve is overridden and the position of the manual control valve determines the direction in which the fluid motor will move. The pilot operated control valve of the present invention also allows the pressurized fluid to flow therethrough such that the pressurized fluid may be used by other successive fluid systems in fluid communication therewith.

The pilot portion of the control valve includes a body having a chamber therein. The chamber houses a piston which divides the chamber into a first chamber portion and a second chamber portion. The first chamber portion is adapted to receive a signal from the binary control valve and the second chamber portion is adapted to receive a signal from the manual control valve.

A passageway interconnects the first chamber portion and second chamber portion such that when a signal is received from the binary control valve, pressurized fluid moves the piston in one direction and a small portion of fluid flows from the first chamber portion to the second chamber portion. The fluid received by the second chamber portion normally flows into a reser voir. However, when the manual control valve is actuated, the reservoir is blocked from the second chamber portion so that the pressurized fluid received by the second chamber portion from the first chamber portion acts to move the piston in the opposite direction against the fluid flow since the area of the pressure face of the piston defining a portion of the second chamber portion is greater than the area of the pressure face defining a portion of the first chamber portion.

The fluid system of the present invention provides a manual override control when the fluid system is in the automatic or first operational mode which provides a safety feature. When the fluid system of the present invention is used in a machine, the direction of the movement of the fluid motor may be reversed by the manual control valve by simply blocking the flow of fluid from the second chamber portion to the reservoir. Thus, if

an emergency situation arises, such as a jammed ma- 5 chine, or the operator being in a dangerous position, the machine may be stopped and reversed by activating the manual control valve.

The manual override of the present invention reverses the direction of movement of the fluid motor at a much lower rate than its normal operation, since the passageway connecting the chamber portion to the second chamber is relatively small in comparison with the size of the opening admitting fluid pressure to the first chamber portion. This provides an even, slow movement of the fluid motor in the opposite direction.

This manual override is positive in action and does not depend on anything more than merely blocking the second chamber portion from its reservoir and effectively provides a positive link between the manual control valve and the pilot operated control valve. Such a system is relatively failproof in operation.

The fluid system of the present invention also includes a selector valve to provide power to the binary control valve such that a signal may be provided from the binary control valve to the pilot operated control valve. The selector valve is also positionable to remove power from the binary control valve'and provide power to the manual control valve such that the pilot operated control valve may be manually operated by the manual valve.

Yet another safety feature of the present invention resides in the fact that the selector valve may be moved to the manual position such that power is no longer received by the binary control valve. Thus, the pilot operated control valve is no longer actuated or controlled by the binary control valve, and therefore is no longer in the automatic operational mode. When this situation exists, the manual control valve may be so positioned so as to receive power from the selector valve and provide power to the pilot operated control valve.

The manually operable feature of the present invention allows separate operations to be manually actuated in a sequence other than would occur in the automatic or first operational mode.

Accordingly, it is an object of the present invention to provide a new and improved fluid system having a pilot operated control valve for automatically operating a fluid motor in an automatic or first operational mode and which is adapted to receive a signal tooverride the first operational mode.

A further object of the present invention is to provide a new and improved fluid system having a pilot operated control valve for automatically controlling a fluid motor in an automatic or first operational mode and adapted to receive a signal which overrides the first operational mode from a manually controlled valve.

A still further object of the present invention is to provide a new and improved fluid system for automatically controlling a fluid motor and having a pilot operated control valve for automatically controlling the fluid motor in an automatic or first operational mode and wherein the pilot operated control valve is adapted to receive a signal from a manual control valve to override the automatic control of the fluid motor and re verse the direction in which it is moving.

Another object of the present invention is to provide a new and improved fluid system having a pilot operated control valve for automatically controlling a fluid motor in an automatic or first operational mode and which control valve includes a pilot portion having a chamber receiving a piston which divides the chamber into a first chamber portion and a second chamber portion, and wherein the first portion is adapted to receive a signal from an automatic control sensor for automatically controlling the direction of movement of the fluid motor by controlling the flow of pressurized fluid into the first chamber portion and whereby the second chamber portion is adapted to receive a signal from a manual control valve which is effective by blocking the second chamber portion from fluid communication with a reservoir such that when the manual control valve blocks the second chamber portion from the reservoir, the pressurized fluid flowing from the first chamber portion to the second chamber portion through an interconnecting passageway moves the piston in the other direction to reverse the movement of the fluid motor.

A further object of the present invention is to provide a new and improved fluid system having a pilot operated control valve for automatically controlling a fluid motor in an automatic or first operational mode and adapted to receive a signal from a pilot control valve for controlling movement of the fluid motor in one direction.

Yet another object of the present invention is to provide a new and improved fluid system having a pilot operated control valve for automatically controlling a fluid motor in an automatic or first operational mode and adapted to receive signals from a plurality of automatic control valves for moving the fluid motor in one direction or the other in an automatic operational sequence and also adapted to receive a signal from a manually controlled valve for manually overriding the signals received by the automatic control valves so that the fluid motor is stopped and moved in a direction opposite the direction provided for by the signals received by the automatic control valves.

Further objects, advantages and features of the present invention will be apparent to those skilled in the art to which it relates from the following detailed description made with reference to the accompanying drawings forming a part of the specification and in which:

FIG. 1 is a schematic view of the fluid system of the present invention including a pilot operated control valve;

FIG. 2 is a cross-sectional view of the pilot operated control valve shown in FIG. 1 in one position; and

FIG. 3 is a cross-sectional view of the pilot operated valve shown in FIG. 1 in another position.

The present invention provides a fluid system for use with a fluid motor which is operated automatically in a first operational mode by a pilot operated control valve associated with at least one sensor or binary valve. A manually operated valve is associated with the pilot operated control valve to provide a signal to the pilot operated control valve to override the automatic control of the fluid motor by the binary valve. The fluid system of the present invention provides an override control for removing the fluid motor from automatic control and reversing the direction thereof. A separate selector valve is also provided as an added safety feature which allows the direction of the fluid motor to be controlled by the manually controlled valve. The present invention may be applied to fluid systems of a wide variety of constructions and designs and for purposes of illustration, is described in the drawings as applied to a representative fluid system 10, as shown in FIG. 1.

The fluid system 10 of the present invention is used in conjunction with a fluid motor 12 for automatically operating the fluid motor 12 in an automatic or first operational mode and to this end, includes a manually controlled valve 14. The fluid flow to the motor 12 is controlled by a pilot operated control valve, generally indicated at 16, having a control valve portion 18 for conducting pressurized fluid from a pressurized fluid supply 20 to the fluid motor 12 in a predetermined manner such that the fluid motor 12 moves in a predetermined direction. The pilot operated control valve 16 also includes a pilot portion 22 associated with the control valve portion 18 for controlling the control valve portion 18 and thereby controlsthe direction of movement of the fluid motor 12.

First and second binary control valves or sensors 24, 26, respectively, are operatively associated with the pilot portion 22 of the pilot operated control valve 16. The binary control valves 24,26 each have a first portion, generally indicated at 28, to control the pilot operated control valve 16 by transmitting a fluid signal thereto and thereby effecting operation of the fluid motor 12 in one direction. The binary control valves or sensors 24, 26 have a second portion, generally indicated at 30, in which no signal is transmitted to the pilot operated control valve 16.

For example, when a signal is provided by the binary control valve 24 and the binary control valve 24 has the first portion 28 positioned to direct fluid therethrough, a signal is received by the pilot valve portion 22 to position the control valve portion 18 such that the fluid motor 12 is moved in one direction. It is to be understood that when the fluid motor 12 is moved to a position, the binary control valve 24 is then actuated so that its second portion blocks flow through the valve from the supply and fluid is received thereby from the pilot valve portion and returned to a reservoir, generally indicated at 32.

Even though the above describes the use of only the binary control valve 24, it should be understood that the binary control valve 26 operates in a similar manner. Additional binary control valves may also be used in the automatic mode, but for simplifying the description of the fluid system, only two binary control valves are shown.

As noted above, the motor 12 is operated by fluid flow from pump 20 through valve portion 18 of the control valve 16. The valve portion 18 is controlled by the pilot portion 22 of the control valve 16. In turn, the pilot portion 22 of the control valve 16 is controlled by binary valves 24, 26. In the present embodiment, the

binary valves 24, 26 control the valve portion 18 to cause the motor 12 to operate in opposite directions.

The binary valves 24, 26' may be operated in a variety of different ways. Preferably, the present system forms a part of a control system for a machine having sequentially operated parts, the motor 12 providing the power for operating the parts. The binary valves are operated in timed relation by cams, solenoids, etc., (not shown) to thereby control the operation of the motor 12 automatically and in a first operational mode. The cams, so-

lenoids, etc., operate the valves 24, 26 to locate either portion 28 or 30 thereof in the desired positions.

When the fluid system is in the automatic operational mode, the pump is supplying pressurized fluid to the control valve portion 18 of the pilot operated control valve 16 and dependent on the position of the control valve portion, is operable to move the fluid motor 12 in one direction. It should be understood that the fluid motor 12 may be of any design well known to those skilled in the art and for purposes of schematic representation, this application shows it as a reciprocating cylinder having fluid supplied to one end by the conduit 34 and to the other end by the conduit 36.

Depending on the position of the pilot operated control valve 16, fluid pressure is supplied through one of the conduits 34, 36 and the fluid displaced by the fluid motor 12 as it moves and is returned to the control valve portion 18 through the other conduit and then to a reservoir 38. I

In order to determine the direction in which the motor 12 moves, the control valve portion 18 is operatively associated with the pilot valve portion 22 to position the control valve portion 18 and thereby determine the direction in which the fluid motor 12 is to move.

A control pump 40 is provided to supply pressurized fluid to the binary control valves or sensors 24, 26, and the manually operated control valve 14 is provided for control of the pilot operated control valve 16. The pressurized fluid flowing from the control pump 40 flows through a conduit 42 to a selector valve 44.

The selector valve 44 has a first position, generally indicated at 46, for supplying the pressurized fluid to the binary control valves or sensors 24, 26 and blocks any fluid flow through or to manually operated control valve 14. The pressurized fluid flows from the selector valve when in the position 46, communicates with the conduit 50, to the binary control valves or sensors 24, 26. Thus, the fluid motor 12 may be operated in an automatic or first operational mode by the transmission of signals from the sensors 24, 26 to the pilot portion 22 of the pilot operated control valve 16.

The selector valve 44 also has a second portion 48 which is positionable to supply pressurized fluid to the manual control valve 14 and block flow of pressurized fluid to the binary control valves or sensors 24, 26. When the selector valve 44 is in such a position, the direction of operation of the fluid motor 12 is manually controlled by the manual control valve 14. When this condition exists, the system 10 is not in an automatic operational mode and the binary control valves or sensors 24, 26 have no effect on the direction in which the fluid motor 12 moves, since they cannot supply a signal to the pilot operated control valve 16.

A pressure release valve 52 is provided for diverting In the automatic operational mode, pressurized fluid is supplied to the binary valves 24, 26 through the conduit 50. The binary control valves or sensors 24, 26 are connected to the pilot valve portion 22 of the pilot operated control valve 16 by means of conduits 56, 58, respectively. When the fluid system 10 of the present invention is used in conjunction with a mechanism, the binary control valves or sensors 24, 26 are positioned with respect to the mechanism such that they will actuate the pilot operated control valve 16 when it is desirable to move the fluid motor 12 in one direction or the other. It should be understood that the binary control valves or sensors 24, 26 are biased in one direction such that they are in a normal position so that the conduits 56, 58 connected to the pilot operated control valve 16 are normally connected to the reservoir 32. It

should further be understood that the binary control valves or sensors 24, 26 are merely representative and any signal device or sensor may be used which provides a signal to the pilot operated control valve 16 upon actuation.

In operation, when the binary control valve 24 is moved by the associated mechanism from the normal position to the first position 38, the fluid pressure re- I control valve portion 18 and the conduit 36, and, thus,

the fluid motor 12 is moved upwardly, as viewed in FIG. 1. The conduit 34 then directs fluid from the the pressurized fluid supplied by the control pump 40 to a reservoir 54 when an excessive amount of pressure is created by the control pump 40. The pressure release valve 52 is adjustable and is of a construction well known to those skilled in the art and is not an essential element of the fluid system 10 of the present invention. At this point, it should further be understood that the selector valve 44 is not essential to the manual override by the manually operated control valve 14 over the automatic operational mode created by the automatic operation of the pilot operated-control valve 16 by the binary valves 24, 26.

upper end of the cylinder to the control valve portion 18 from which it is directed to the reservoir 38 by the conduit 60.

When the binary control valve 26 ismoved by the associated mechanism, fluid pressure is supplied from the control pump 40, through the conduit 50, binary control valve 26 and conduit 58 to the pilot valve portion 22 of the pilot operated control valve 16. The pilot valve portion 22 positions the control portion 18 of the pilot operated control valve 16 to supply fluid pressure from the pump 20 through the control valve portion 18 and conduit 34, to the fluid motor 12'to move the fluid motor downwardly, as viewed in FIG. 1. The conduit 36 receives fluid from the fluid motor 12 and it is returned through the control valve portion 18 and conduit 60 to the reservoir 38.

As the binary control valves or sensors 24, 26 are sequentially activated and deactivated by the associated mechanism, the fluid motor 12 moves in an automatic or operational mode dependent .on the respective positions of the binary control valves or sensors 24, 26. It should be understood that additional binary control valves maybe added to such a system for controlling the direction in which the fluid motor moves.

When the fluid motor 12 is in automatic operational mode, the pilot valve portion 22 is connected to the manually operated control valve 14 by the conduits 62, 64. When the fluid system 10 is in the automatic operational mode, both of the conduits 62, 64 are connected to a reservoir 66 through the manually operated control valve when the manually operated control valve is in a position with its portion 68 in the position shown in FIG. 1.

The manually operated control valve 14 is normally in the position shown in FIG. 1 so that the fluid system 10 is normally in an automatic operational mode. The manual control valve 14 is positionable in first or second overriding positions, respectively. The valve 14 includes portions 70, 72 which may be moved into operative position communicating with conduits 62, 64. When these portions are so positioned, the valve is in its first or second overriding position.

When the fluid system 10 is in the automatic operational mode, the binary valve 24 is positioned so that pressurized fluid is supplied to the pilot valve portion 22 of the pilot control valve 16 through the conduit 56 to activate the control valve portion 18 such that the fluid motor 12 is moved in one direction. When the manually controlled override valve 14 is activated so as to position portion 70 in communication with conduits 62, 64, the conduit 62 is blocked and is no longer connected to the reservoir 66. The blocking of the passageway 62 provides a signal to the pilot operated control valve 16 so that the pilot operated control valve 16 reverses the direction of the flow of the pressurized fluid into the fluid motor 12 to thereby reverse the direction of movement of the fluid motor 12.

On the other hand, when the binary valve 24 is in a normal position 30 and the binary control valve 26 is positioned so that pressurized fluid is supplied to the pilot operated control valve 16, through the conduit 58, the pilot operated control valve is positioned such that fluid is supplied from the pump 20 to the fluid motor 12 to move the fluid motor, as described above. When it is desirable to override the valve 26, the manually operated control valve 14 is positioned so that portion 72 communicates with the conduits 62, 64. When portion 72 is so positioned, it blocks the passageway 64 and connects the passageway 62 to the reservoir 66 and thereby provides a signal to the pilot operated control valve 16 such that the direction of the fluid motor 12 is reversed, as hereinafter described.

The selector valve 44 may be positioned so that the portion 48 thereof is connected with the pump 40. When the selector valve is so positioned, no fluid is supplied to the binary control valves or sensors 24, 26 and thus the valves 24, 26 cannot provide a signal to the pilot operated control valve 16 to automatically cycle the fluid motor 12. Also when the selector valve 44 is so positioned, the manual control valve 14 is supplied with fluid from pump 40. When in its normal position, as shown in FIG. 1, the fluid supplied to the manual control valve 14 is returned to the reservoir 66. When the manually operated control valve 14 is positioned with portion 70 communicating with conduits 62, 64 pressurized fluid is supplied to the pilot operated control valve 16 through the conduit 62, and conduit 64 is connected to the reservoir, thereby positioning the pilot operated control valve so that the fluid motor 12 moves in one direction. When the manually operated control valve is positioned with portion 72 communi-.

eating with conduits 62, 64, the pressurized fluid is supplied to the pilot operated control valve 16 through the conduit 64, and the conduit 62 is connected to the reservoir 66 so that the fluid motor 12 moves in the other direction. This feature provided by the selector valve 44 allows the system to be manually controlled completely independently of the binary control valves or sensors 24, 26.

The pilot operated control valve 16 throughout the operation allows pressurized fluid'to flow from the pump 20, through the conduit 74, to a subsequent fluid system, regardless of the position of the pilot operated control valve 16, and thereby comprises an opencenter valve 16. FIG. 2 shows the pilot operated control valve 16 in one position. When in this position, pressurized fluid is received by the pilot operated control valve.

The pilot valve portion 22 is defined by a body 82 having chambers 84, 86. The chamber 84 is divided into first and second portions 88, 94 by piston 80, and the chamber 86 is divided into first and second chamber portions 90, 92, respectively, by piston 80a. Pistons 80, 80a have passageways 96, 98, respectively, interconnecting the first and second chamber portions 88, 94 and 90, 92, respectively, so that when fluid is supplied to the first chamber portions 88, 90, pressurized fluid is also supplied to the second chamber portions 94, 92. Thus, when fluid pressure is supplied from the binary control valve 26, through the conduit 58, to the first chamber portion 90, the piston 80a moves to a position as shown in FIG. 2. As the piston 80a moves to that position, pressurized fluid flows through the passageway 98 into the second chamber portion 92, and subsequently from the second chamber portion, through the conduits 64, to the reservoir 66 when the manually operated control valve 14 is in the normal position 68, shown in FIG. 1. The fluid in the first chamber portion 88 and second chamber portion 94 are each connected to the reservoirs 32, 66, respectively, through the conduits 56, 62, respectively, and do not provide any moving force to position the piston member 80. It should further be understood that the piston 80 is moved to the position as shown in FIG. 2 by the force of the pressurized fluid in the first chamber portion 90 exerted on the pressure face indicated at 100 of the piston 80a.

When the pilot operated control valve 16 is in the position as shown in FIG. 2,.the piston member 800 is connected with a valve stem in the body 104 of the control valve portion 18 so that when the piston 80a moves, the control valve portion 18 is effectively controlled thereby. The control valve portion 18 receives pressurized fluid from the pump 20 by means of the conduit 106 which communicates with a passageway 108. The passageway 108 is connected to the conduit 74 to allow fluid to flow directly from the pump 20 to subsequent fluid valves or systems and thereby the valve 18 is an open-center valve.

The fluid flows through the passageway 108 to a I chamber 110 and a chamber 112. The chamber 112 is connected to the conduit 36 and, consequently, supplies pressurized fluid thereto. The piston member has a portion 114 which permits fluid to flow through the space defined between the chamber and chamber 112, and the body 104 and portion 114. Thus, pressurized fluid is supplied to the fluid motor 12 through the conduit 36 in the position shown in FIG. 2.

conduit 34, which is in turn connected to the other side of the fluid motor 12. A portion 124 of the valve stem provides a passageway connecting the chamber 122 with the conduit 60 so as to allow the portion of the fluid motor 12 in communication with the conduit 34 to be in fluid communication with the reservoir 38- through conduit 60. It should be understood that when the piston 80a and valve stem are in the condition shown in FIG. 2, the portion 128 of the valve stem has a seating relationship with the body 104 and prevents the conduit 36 from being in communication with the reservoir 38 through the chamber 112 and the conduit 60.

The valve stem has an end portion 130 which has a seating ring, such as a split ring 132, and members 134, 136 thereon. A spring 142 is interposed between the members 134, 136. The members 134, 136 are axially movable relative to the valve stem and are engageable with the split ring 132 and shoulder 124, respectively. The spring 142, as should be apparent urges the valve stem to a normal or centrally located position in which fluid is not permitted to flow to the fluid motor 12 in either conduit 34 or 36. ltshould be understood that when the piston 80 is in the centered position, the portion 114 and 118 have a sealing relationship with portions 104a, 104b of the body 104 so that fluid is blocked from flowing from the pump to the fluid motor 12.

It should be understood that when the valve stem is positioned as shown in FIG. 2, the member 136 and spring 142 exert a force on the valve stem in a direction tending to move the valve stem to the neutral position, and, on the other hand, when the valve stem is in a position as shown in FIG. 3, the member 134 acts against the retaining ring 132 to force the valve spring to the neutral position.

As noted above, if some emergency should arise where it is necessary to override the automatic control, the manually operated control valve 14 may be moved to locate portion 72 of the valve 14 in contact with the conduits 62, 64. As a result, the fluid normally flowing through the conduit 64 to the reservoir 66 is blocked. Prior to this, the pressurized fluid is flowing through the conduit 58, chamber 90, the passageway 98, and into the second chamber portion 92 of the pilot valve portion 22. Since the second chamber portion 92 is now blocked by operation of the valve 14 from fluid communication with the reservoir 66, a pressure is built up in the second chamber portion 92 to substantially equalize the pressure in chamber 90.

Since the pressure face 102 of the piston 80 defining a portion of the second chamber portion 92 has a greater area than the pressure face 100, the piston 80 moves toward a position, as shown in FIG. 3, and thereby reverses the flow of fluid through the control valve portion 18 and the direction of the fluid motor 12. Thus, this constitutes a manual override for the automatic operation of the valve 16.

When the second chamber portion 92 of the pilot control valve portion 22 is blocked from the reservoir 66, the piston 80a cannot move from the position as shown in FIG. 3 no matter what the condition of the binary control valve or sensor 26. If pressure is supplied from the binary control valve 26 through the conduit 58, the chambers 90, 92 simply increase in pressure due to the transmission of the fluid through the passageway 98 and since the area of pressure face 102 is greater than the area of pressure face 100, the piston 80a is urged further to the right in FIG. 3, but is prevented from further movement by the stop member 116 abutting the valve body 104.

It should be noted that when fluid pressure exists in the first chamber portion 88, a portion of that fluid will flow through the passageway 96 into the second chamber portion 94 and, consequently, to the reservoir 66 through the conduit 62 and manualcontrol valve 14. But this will urge the valve stem to the right, as viewed in the drawings, as should be understood.

It should be understood that when the binary control valve 24 provides a signal to the pilot valve portion 22, the signal received thereby may be overriden by a signal from the manually operated control valve 14 by positioning the manually operated control valve 14 so that the portion 70 thereof communicates with conduits 62,

64. Thus, the conduit 62 is blocked and the piston 80 is moved to a position, as shown in FIG. 2, in a manner similar to that described in connection with the overriding of a signal received by the control valve from binary valve 26 when the manually operated control valve 14 is positioned with portion 72 communicating with conduits 62, 64.

When the selector valve 44 is moved to communicate portion 48 thereof with pump 40, pressurized fluid is no longer supplied through the conduit 50 to the binary control valves 24, 26, but rather is supplied to the manually operated control valve 14. When the manually operated control valve 14 is in the neutral position 68, the pressurized fluid received from the control pump 40 is returned to the reservoir 66.

When the manually operated control-valve 14 is moved to communicate portion 70 with conduits 62, 64, pressurized fluid is supplied through the conduit 62 into the second chamber portion 94 which moves the piston 80 and valve stem to the position generally indicated in FIG. 2, and, consequently, allows pressurized fluid to flow from the pump 20 the the fluid motor 12 through the conduit 36 and connects the conduit 34 from the fluid motor 12 to the reservoir 38. A portion of the pressurized fluid flows through the passageway 96, through the conduit 56 and into the binary control valve 24, and, consequently, into the reservoir-32, but this bleeding action is not significant and does not affect the motion of the piston member 80 or valve stem. The second chamber portion 92 is connected to the reservoir 66 through the conduit 62 and allows the chamber 92 to decrease in volume.

On the other hand, when the manually operated control valve 14 is positioned in the portion 72in communication with the conduits 62, 64, pressurized fluid is supplied to the pilot valve portion 22 through the conduit 64 to provide fluid pressure against the pressure face 102 of the piston a and thereby moves the piston 80a and valve stem to the position shown in FIG. 3 and reverses the motion of the fluid motor 12.

Accordingly, the present invention provides ,a fluid system 10 for use with a fluid motor 12 in which the fluid motor 12 is operated in an automatic or first operational mode under the control of the binary valves 24, 26. The fluid system 10 of the present invention provides a safety override for overriding the automatic operational mode of the fluid motor 12 and reversing the direction of the fluid motor 12. This override device is positive in action and substantially failproof in operation, since the mere blocking of a passageway is suffi-- cient to reverse the direction of the movement of the fluid motor 12. Additional features of the present invention are that a selector valve is included which allows the device to be manually operated.

What I claim is:

l. A fluid system for controlling a fluid motor in a first operational mode through a plurality of binary control valves actuated by automatic means and in a second operational mode by a manually actuated control valve comprising:

a fluid motor;

a pilot operated control valve assembly having a control valve portion for conducting pressurized fluid from a pressurized fluid supply to said fluid motor to effect control of said fluid motor and having a pilot valve portion connected to said control valve portion to control said control valve portion, said control valve portion having a passageway for allowing pressurized fluid to be transmitted to successive fluid systems, said pilot valve portion including a piston member and a body having a chamber therein for receiving said piston member, said piston member dividing said chamber into first and second chamber portions, means for directing fluid pressure into the first chamber portion, and means for directing fluid pressure from the first chamber portion into the second chamber portion, said piston member having a greater pressure face against which the fluid pressure in the second chamber portion acts than the pressure face against which the fluid pressure in the first chamber portion acts; plurality of binary control valves connected to said pilot valve portion to operate said fluid motor in said first operational mode, each of said binary control valves establishing a first signal and a second signal to said pilot operated control valve such that when a first signal is provided by one of said binary control valves or a second signal is provided by another of said binary control valves said pilot operated control valve conducts pressurized fluid to the fluid motor to move the fluid motor in a respective direction during the operation of said system in said first operational mode; a manual control valve for operating said fluid motor in said second operational mode, said manual valve having a neutral position and a second position, said manual valve receiving pressurized fluid transmitted to the second chamber portion from the first chamber portion through said means for directing fluid pressure into the second chamber portion when pressurized fluid is supplied to the first chamber portion, the second position of said manual valve blocking the second chamber portion from fluid communication with the reservoir so that the pressurized fluid received by the second chamber portion from the first chamber portion exerts a force greater than the force exerted by the pressurized fluid in the first chamber portion due to the greater pressure face area, said manual control valve further including means for blocking fluid flow in a conduit means for normally directing fluid from said second chamber to a low pressure reservoir;

selector valve for switching the operation of said fluid motor between said first operational mode and said second operational mode by supplying pressurized fluid to either said manual control valve or said binary control valve to exclusively operate the valve supplied with said pressurized fluid; and

said manual control valve including means for overriding the control of said control valve through said binary control valves during the first operational mode and reversing the direction of said fluid motor movement to an opposite direction upon actuation of said override means.

2. A fluid system for independently controlling a fluid motor in either a first operational mode by binary control valves actuated by an automatic means or in a second operational mode. by a control valve actuated by manual means comprising:

a fluid motor;

a pilot operated control valve assembly having a control valve portion for conducting pressurized fluid from a pressurized fluid supply to the fluid motor to effect operation of the fluid motor and a pilot valve portion connected to said control valve portion including a chamber containing an opposed differential area pressure responsive means and provided with passage means communicating said opposite areas with one another for controlling said control valve portion;

binary control valves connected to said pilot valve portion of said pilot operated control valve to actuate said pilot valve portion in response to signals from the automatic means to control said fluid motor through said control valve portion in said first automatic operational mode;

a manual control valve connected to said pilot valve portion for actuating said pilot valve portion in response to a control signal from the manual means to thereby control said fluid motor through said control valve portion in said second manual operational mode; selector valve for switching the operation of said fluid motor between said first operational mode and said second operational mode by supplying pressurized fluid to either said manual control valve or said binary control valve to thereby provide exclusive operation of said pilot valve portion either by said manual control valve or by said binary control valves; and

said manual control valve including means, connected to said pilot valve portion of said pilot operated control valve, for overriding the automatic operational mode selected by said selector valve and reversing the direction of fluid motor movement existing in the automatic operational mode selected by said selector valve to an opposite direction.

3. A fluid system as defined in claim 2 in which said pilot portion includes a piston member defining said pressure responsive means and a body having said chamber therein for receiving said piston member, said piston member dividing said chamber into first and second chamber portions, means for directing fluid pressure into the first chamber portion, and said passage means directs fluid pressure from the first chamber portion into the second chamber portion, said piston member having a greater pressure face against which the fluid pressure in the second chamber portion acts than the pressure face against which the fluid pressure in the first chamber portion acts.

4. A fluid system as defined in claim 3 wherein said manual valve has a neutral position and at least a second position, said manual valve is adapted to receive pressurized fluid transmitted to the second chamber portion from the first chamber portion through said passage means directing fluid pressure into the second chamber portion when pressurized fluid is supplied to the first chamber portion, the second position of said manual valve effecting blocking of the second chamber portion from fluid communication with the reservoir so that the pressurized fluid received by the second chamber portion from the first chamber portion exerts a force greater than the forced exerted by the pressurized fluid in the first chamber portion due to the greater pressure face area.

5. A fluid system'as defined in claim 4, including con- I duit means normally directing fluid from said second chamber to a low pressure reservoir, said manual control valve, being operative to block fluid flow in said conduit means.

6. A fluid system for controlling a fluid motor as defined in claim 5 wherein said control valve portion of said pilot operated control valve includes a passageway therethrough for allowing the pressurized fluid to be transmitted to successive fluid systems.

UNITED STATES 'PATENT OFFICE CERTIFICATE OF CORRECTION patent 3,8h7,060 Dated- November 12, 1974 Inventor (s) Stanley C Jasinski It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

[76] Inventors should properly be numbered Column 5, line 6, after "first" insert chamber Column 6, line 2h, "58" should read-'- 28 Signed and sealed this 22nd day of April 1975.

(SEAL) Attest:

C. MARSHALL DANN RUTH C. MASON Commissioner of Patents Attesting Officer and Trademarks USCOMM-DC 60376-P69 FORM PO-105O (IO-69) u.s. covsnuuzm- PRINTING orncz; 930 

1. A fluid system for controlling a fluid motor in a first operational mode through a plurality of binary control valves actuated by automatic means and in a second operational mode by a manually actuated control valve comprising: a fluid motor; a pilot operated control valve assembly having a control valve portion for conducting pressurized fluid from a pressurized fluid supply to said fluid motor to effect control of said fluid motor and having a pilot valve portion connected to said control valve portion to control said control valve portion, said control valve portion having a passageway for allowing pressurized fluid to be transmitted to successive fluid systems, said pilot valve portion including a piston member and a body having a chamber therein for receiving said piston member, said piston member dividing said chamber into first and second chamber portions, means for directing fluid pressure into the first chamber portion, and means for directing fluid pressure from the first chamber portion into the second chamber portion, said piston member having a greater pressure face against which the fluid pressure in the second chamber portion acts than the pressure face against which the fluid pressure in the first chamber portion acts; a plurality of binary control valves connected to said pilot valve portion to operate said fluid motor in said first operational mode, each of said binary control valves establishing a first signal and a second signal to said pilot operated control valve such that when a first signal is provided by one of said binary control valves or a second signal is provided by another of said binary control valves said pilot operated control valve conducts pressurized fluid to the fluid motor to move the fluid motor in a respective direction during the operation of said system in said first operational mode; a manual control valve for operating said fluid motor in said second operational mode, said manual valve having a neutral position and a second position, said manual valve receiving pressurized fluid transmitted to the second chamber portion from the first chamber portion through said means for directing fluid pressure into the second chamber portion when pressurized fluid is supplied to the first chamber portion, the second position of said manual valve blocking the second chamber portion from fluid communication with the reservoir so that the pressurized fluid received by the second chamber portion from the first chamber portion exerts a force greater than the force exerted by the pressurized fluid in the first chamber portion due to the greater pressure face area, said manual control valve further including means for blocking fluid flow in a conduit means for normally directing fluid from said second chamber to a low pressure reservoir; a selector valve for switching the operation of said fluid motor between said first operational mode and said second operational mode by supplying pressurized fluid to either said manual control valve or said binary control valve to exclusively operate the valve supplied with said pressurized fluid; and said manual control valve including means for overriding the control of said control valve through said binary Control valves during the first operational mode and reversing the direction of said fluid motor movement to an opposite direction upon actuation of said override means.
 2. A fluid system for independently controlling a fluid motor in either a first operational mode by binary control valves actuated by an automatic means or in a second operational mode by a control valve actuated by manual means comprising: a fluid motor; a pilot operated control valve assembly having a control valve portion for conducting pressurized fluid from a pressurized fluid supply to the fluid motor to effect operation of the fluid motor and a pilot valve portion connected to said control valve portion including a chamber containing an opposed differential area pressure responsive means and provided with passage means communicating said opposite areas with one another for controlling said control valve portion; binary control valves connected to said pilot valve portion of said pilot operated control valve to actuate said pilot valve portion in response to signals from the automatic means to control said fluid motor through said control valve portion in said first automatic operational mode; a manual control valve connected to said pilot valve portion for actuating said pilot valve portion in response to a control signal from the manual means to thereby control said fluid motor through said control valve portion in said second manual operational mode; a selector valve for switching the operation of said fluid motor between said first operational mode and said second operational mode by supplying pressurized fluid to either said manual control valve or said binary control valve to thereby provide exclusive operation of said pilot valve portion either by said manual control valve or by said binary control valves; and said manual control valve including means, connected to said pilot valve portion of said pilot operated control valve, for overriding the automatic operational mode selected by said selector valve and reversing the direction of fluid motor movement existing in the automatic operational mode selected by said selector valve to an opposite direction.
 3. A fluid system as defined in claim 2 in which said pilot portion includes a piston member defining said pressure responsive means and a body having said chamber therein for receiving said piston member, said piston member dividing said chamber into first and second chamber portions, means for directing fluid pressure into the first chamber portion, and said passage means directs fluid pressure from the first chamber portion into the second chamber portion, said piston member having a greater pressure face against which the fluid pressure in the second chamber portion acts than the pressure face against which the fluid pressure in the first chamber portion acts.
 4. A fluid system as defined in claim 3 wherein said manual valve has a neutral position and at least a second position, said manual valve is adapted to receive pressurized fluid transmitted to the second chamber portion from the first chamber portion through said passage means directing fluid pressure into the second chamber portion when pressurized fluid is supplied to the first chamber portion, the second position of said manual valve effecting blocking of the second chamber portion from fluid communication with the reservoir so that the pressurized fluid received by the second chamber portion from the first chamber portion exerts a force greater than the forced exerted by the pressurized fluid in the first chamber portion due to the greater pressure face area.
 5. A fluid system as defined in claim 4, including conduit means normally directing fluid from said second chamber to a low pressure reservoir, said manual control valve being operative to block fluid flow in said conduit means.
 6. A fluid system for controlling a fluid motor as defined in claim 5 wherein said control valve portion of said pilot operated control valve Includes a passageway therethrough for allowing the pressurized fluid to be transmitted to successive fluid systems. 